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{{#Wiki_filter:,gccE~~TEDD1.'>1;jEIUTIONDEMONSTR~TeINSYSTEMREGULATORYINFORMATIONDISTRIBUTIONSYSTEM(RIDS)ACCESSIONNBR:8903150532DOC.DATE:89/03/06NOTARIZED-YESDOCKETgFACIL'.50-244RobertEmmetGinnaNuclearPlant,Unit1,RochesterG05000244AUTH.NAMEAUTHORAFFILIATIONMECREDY,R.C.RochesterGas&ElectricCorp.RECIP.NAMERECIPIENTAFFILIATIONSTAHLE,C.NRC-NoDetailedAffiliationGiven
{{#Wiki_filter:,gccE~~TED D1.'>1;jEIUTION DEMONSTR~TeIN SYSTEMREGULATORY INFORMATION DISTRIBUTION SYSTEM(RIDS)ACCESSION NBR:8903150532 DOC.DATE:
89/03/06NOTARIZED-YESDOCKETgFACIL'.50-244 RobertEmmetGinnaNuclearPlant,Unit1,Rochester G05000244AUTH.NAMEAUTHORAFFILIATION MECREDY,R.C.
Rochester Gas&ElectricCorp.RECIP.NAME RECIPIENT AFFILIATION STAHLE,C.
NRC-NoDetailedAffiliation Given


==SUBJECT:==
==SUBJECT:==
Discussesobjectivesofutilprogramtoconfirmpressurizersurgelineintegrity,perNRCBulletin88-011.DISTRIBUTIONCODE:IE11DCOPIESRECEIVED:LTRENCLSIZE:TITLE:BulletinResponse(50DKT)NOTES:LicenseExpdateinaccordancewith10CFR2,2.109(9/19/72).05000244RECIPIENTIDCODE/NAMEPD1-3LASTAHLE,CINTERNAL:AEOD/DOANRR/DEST/ADE8HNRR/DEST/MEB9HNRR/DOEA/GCB11QJGkSQDLRB12GN1ILE01EXTERNAL:LPDRNSICCOPIESLTTRENCL1011111111111111111111RECIPIENTIDCODE/NAMEPD1-3PDAEOD/DSP/TPABNRR/DEST/ADS7ENRR/DOEA/EAB11NRR/DREP/EPB10NUDOCS-ABSTRACTRES/DSIR/EIBNRCPDRCOPIESLTTRENCL111111111111111'.1NOTE'IOALL"RIDS"RECIPZEÃIS:PLEASEHELPUSTOREDUCEWASTE!CONTACT'IHEDOCUMEMI'GÃIBOLDESK,RXMPl-37(EXT.20079)IOELQ~TEARKNAMEFRYDISTEKBVZIGNLISTSFORDOCt2KMISYOUDGN~TNEEDfTOTALNUMBEROFCOPIESREQUIRED:LTTR19ENCL18 March6,1989U.S.NuclearRegulatoryCommissionDocumentControlDeskAttn:Mr.CarlStahlePWRProjectDirectorateNo.1Washington,D.C.20555
Discusses objectives ofutilprogramtoconfirmpressurizer surgelineintegrity,per NRCBulletin88-011.DISTRIBUTION CODE:IE11DCOPIESRECEIVED:LTR ENCLSIZE:TITLE:BulletinResponse(50DKT)NOTES:License Expdateinaccordance with10CFR2,2.109(9/19/72).
05000244RECIPIENT IDCODE/NAME PD1-3LASTAHLE,CINTERNAL:
AEOD/DOANRR/DEST/ADE 8HNRR/DEST/MEB 9HNRR/DOEA/GCB 11QJGkSQDLRB12GN1ILE01EXTERNAL:
LPDRNSICCOPIESLTTRENCL1011111111111111111111RECIPIENT IDCODE/NAME PD1-3PDAEOD/DSP/TPABNRR/DEST/ADS 7ENRR/DOEA/EAB 11NRR/DREP/EPB 10NUDOCS-ABSTRACT RES/DSIR/EIB NRCPDRCOPIESLTTRENCL111111111111111'.1NOTE'IOALL"RIDS"RECIPZEÃIS:
PLEASEHELPUSTOREDUCEWASTE!CONTACT'IHEDOCUMEMI'GÃIBOL DESK,RXMPl-37(EXT.20079)IOELQ~TEARKNAMEFRYDISTEKBVZIGN LISTSFORDOCt2KMIS YOUDGN~TNEEDfTOTALNUMBEROFCOPIESREQUIRED:
LTTR19ENCL18 March6,1989U.S.NuclearRegulatory Commission DocumentControlDeskAttn:Mr.CarlStahlePWRProjectDirectorate No.1Washington, D.C.20555


==Subject:==
==Subject:==
NRCBulletinNo.88-11AlternateScheduleforEvaluationofPressurizerSurgeLineThermalStratificationR.E.GinnaNuclearPowerPlantDocketNo.50-244
NRCBulletinNo.88-11Alternate ScheduleforEvaluation ofPressurizer SurgeLineThermalStratification R.E.GinnaNuclearPowerPlantDocketNo.50-244


==DearMr.Stahle:==
==DearMr.Stahle:==
OnDecember20,1988,theNRCissuedBulletinNo.88-11"PressurizerSurgeLineThermalStratification".Itrequestsalladdresseestoestablishandimplementaprogramtoconfirmpressurizersurgelineintegrityinviewoftheoccurrenceofthermalstratification,andrequiresthemtoinformthestaffoftheactionstakentoresolvethisissue.PursuanttosatisfyingtherequirementsandschedulesofBulletin88-11,RochesterGasandElectricCorporationisparticipatinginaprogramforpartialresolutionofthisissuethroughtheWestinghouseOwner'sGroup(WOG).TheWOGprogramwasapprovedattheOctober1988meetingandhasthefollowingobjectives:~DevelopagenericJustificationforContinuedOperation(JCO)toassurethatplantsafetyisnotcompromisedwhiletheeffectsofthermalstratificationarebeingdetermined.Collectandsummarizerelevantdesign,operational,analytical,andtestdataforasmanyWOGplantsaspossible.Inaddition,arepresentativesampling,ofapproximatelytenplants,willbeselectedtoperformareviewofplantrecordsandconductinterviewswithoperationspersonnel.~Evaluatedataandidentifyandprioritizesignificantparameterscontributingtothisissue.Categorize(group)~~plplantsbasedontheseparameters.w'0~~'203i5053239030'~PDFAGOCK0.":000244  
OnDecember20,1988,theNRCissuedBulletinNo.88-11"Pressurizer SurgeLineThermalStratification".
~RecommendadditionalmonitoringtosupplementtheexistingtransientdatabaserequiredtoboundallWOGplants.Estimatetheeffectofthermalstratificationonfatiguelifeasafunctionofkeyparameters.~Recommendshorttermandlongtermactions.TheWOGprogramisdesignedtobenefitfromtheexperiencegainedintheperformanceofseveralplant.-specificanalysesonWestinghousePWRsurgelines.Thesedetailedanalysesincludeddefinitionofrevisedthermaltransients(includingstratification)andevaluationsofpipestress,fatigueusagefactor,thermalstriping,fatiguecrackgrowth,leak-before-break,andsupportloads.Theoverallanalyticalapproachusedinalloftheseanalyseshasbeenconsistentandhasbeenreviewed,indetail,bytheNRCstaff.Asignificantamountofsurgelinethermalmonitoringdatahasbeenobtainedinsupportoftheseplant-specificanalyses.AdditionalsurgelinethermalmonitoringandplantsystemdatacontinuestobemadeavailablewithintheWOG,resultinginasteadilyincreasingdatabase.Asignificantamountofprogresshasbeenaccomplishedtowardmeetingtheseobjectives.Todate,theWOGhascompletedapproximately80-odftheeffortofassemblingplant-specificdesigninformationonalldomesticWestinghousePWRs(55unitstotal);Theeffortwillestablishtherangeofkeydesignparametersandpermitgroupingofplantsbasedontheseparameters.Basedontheinformationassembledtodate,andtheexperiencegainedinplant-specificanalysesandmonitoringprograms,theWOGevaluationhasresultedinthefollowingobservationsregardingplantsimilarityandthermalstratification:1.Thermalstratification(>100'F)hasbeenmeasuredonallsurgelinesforwhichmonitoringhasbeenperformedandwhichhavebeenreviewedbytheWOGtodate(7plants).2.Theamountofstratificationmeasuredanditsvariationwithtime(cycling)varies.Thisvariationhasbeenconservativelyenvelopedandapplicabilitydemonstratedforplant-specificanalyses.AdditionalmonitoringdatarepresentingawiderrangeofsurgelineconfigurationsmaybeneededinordertodemonstratetheapplicabilityofthesethermalstratificationtransientstootherWestinghouseunits.3.Significantfactorswhichcaninfluencethestructuraleffectsofstratificationare:a.Locationanddesignofrigidsupportsand.restraintsb.Pipelayoutgeometryandsizec.Typeandlocationofpipingcomponents 4.AlthoughthematerialandfabricationtechniquesforWestinghousesurgelinesarereasonablyconsistentandofhighquality,thedesignparameterslistedinitem3varyamongWestinghousePWRs.Thisvariationindesignisprimarilyaresultofplant-specificroutingrequirements.Thisvariabilityiscurrentlybeingexaminedinordertoasse'ssthefeasibilityofa.boundinganalysisapproach.TheseobservationsdevelopedthroughtheongoingWOGprogram,indicatethatthedevelopmentofthermalstratificationloadingsandtheevaluationoffatigue,consideringtheseloadings,isacomplexprocess.Therefore,inordertopreciselyevaluatestratification,additionaltimeisneeded.Whilemoretimeisneededtoevaluatethestratificationissueindetail,theNDEinspectionhistoryatR.E.Ginna,aswellasallotherdomesticWestinghousedesignedPWRs,hasnotrevealedanyserviceinduceddegradationinthesurgelinepipingthathasbeenattributedtothermalstratification.Inaddition,alltheplant-specificanalysesperformedtodatethathaveincludedtheloadingsduetostratificationandstripinghavevalidatedthe"leak-before-break"conceptandhavesubstantiateda40-yearplantlife.Thus,aprudentapproachforprovidingadetailedevaluationoftheeffectsofsurgelinestratificationwouldbetofollowtheWOGprogramgroupingevaluationrecommendationsandmonitorasdeterminedtobeappropriate.TheWOGhascompletedagroupingevaluation,forthepurposeofrecommendingalistofadditionalplantswherethermalmonitoringisneeded.Thetimerequiredforthisadditionalmonitoringwillbedependentonplantoutageschedules.Toassurethattheplantsafetyisnotcompromisedwithintherequestedperiodofscheduleextension,aJCOwillbeprepared.TheJCO,whichiscurrentlybeingdeveloped,willbeavailableforstaffreview,ifdesired,within4monthsofreceiptoftheBulletin.TheJCOwillutilizetheinformation,experience,andmonitoringdataobtainedthroughtheWOGprogram,andwillsupportthealternateschedulediscussedherein.RochesterGasandElectricCorporationherebyrequestsanalternatescheduletothatrequestedinBulletin88-11.Ascheduleoftwoyears,fromreceiptoftheBulletin,isconsideredsufficienttimetoobtainthenecessaryadditionalmonitoringdata,definethermaltransients,performallrequiredanalysesandupdatethestressandfatigueanalysestoensurecompliancewithapplicablecodeandregulatoryrequirements.Thisschedule,thoughdifferentfromthatrequestedinaction1.bofBulletin88-11,isconsistentwiththerequirementtoupdatethestressandfatigueanalyseswithintwoyearsasstatedinaction1.do~eBulletin.
Itrequestsalladdressees toestablish andimplement aprogramtoconfirmpressurizer surgelineintegrity inviewoftheoccurrence ofthermalstratification, andrequiresthemtoinformthestaffoftheactionstakentoresolvethisissue.Pursuanttosatisfying therequirements andschedules ofBulletin88-11,Rochester GasandElectricCorporation isparticipating inaprogramforpartialresolution ofthisissuethroughtheWestinghouse Owner'sGroup(WOG).TheWOGprogramwasapprovedattheOctober1988meetingandhasthefollowing objectives:
Atthistime,RochesterGasandElectricCorporation'srequestforanalternatescheduleappliesonlytoitem1.bofNRCBulletin88-11.RochesterGasandElectricCorporationintendstocomplywithallotherrequirementsoftheBulletin,butwillinformthestaffandjustifydifferences,ifappropriate.Verytrulyyours,RobertC.MecedyGeneralManagerNuclearProductionRWEN024Subscribedandsworntobef'oremeonthis6thdayofMarch,1989.JAMESC.McGUiAENTARYPUSUC,StateoiNewYorkOuaIfiedinhbnroeCourttyMgCoinnissionExp@aOec.28,t9'zc:U.S.NuclearRegulatoryCommissionRegionI475AllendaleRoadKingof'Prussia,PA19406GinnaSeniorResidentInspector}}
~DevelopagenericJustification forContinued Operation (JCO)toassurethatplantsafetyisnotcompromised whiletheeffectsofthermalstratification arebeingdetermined.
Collectandsummarize relevantdesign,operational, analytical, andtestdataforasmanyWOGplantsaspossible.
Inaddition, arepresentative
: sampling, ofapproximately tenplants,willbeselectedtoperformareviewofplantrecordsandconductinterviews withoperations personnel.
~Evaluatedataandidentifyandprioritize significant parameters contributing tothisissue.Categorize (group)~~plplantsbasedontheseparameters.
w'0~~'203i5053239030'~PDFAGOCK0.":000244  
~Recommend additional monitoring tosupplement theexistingtransient databaserequiredtoboundallWOGplants.Estimatetheeffectofthermalstratification onfatiguelifeasafunctionofkeyparameters.
~Recommend shorttermandlongtermactions.TheWOGprogramisdesignedtobenefitfromtheexperience gainedintheperformance ofseveralplant.-specific analysesonWestinghouse PWRsurgelines.Thesedetailedanalysesincludeddefinition ofrevisedthermaltransients (including stratification) andevaluations ofpipestress,fatigueusagefactor,thermalstriping, fatiguecrackgrowth,leak-before-break,andsupportloads.Theoverallanalytical approachusedinalloftheseanalyseshasbeenconsistent andhasbeenreviewed, indetail,bytheNRCstaff.Asignificant amountofsurgelinethermalmonitoring datahasbeenobtainedinsupportoftheseplant-specific analyses.
Additional surgelinethermalmonitoring andplantsystemdatacontinues tobemadeavailable withintheWOG,resulting inasteadilyincreasing database.
Asignificant amountofprogresshasbeenaccomplished towardmeetingtheseobjectives.
Todate,theWOGhascompleted approximately 80-odftheeffortofassembling plant-specific designinformation onalldomesticWestinghouse PWRs(55unitstotal);Theeffortwillestablish therangeofkeydesignparameters andpermitgroupingofplantsbasedontheseparameters.
Basedontheinformation assembled todate,andtheexperience gainedinplant-specific analysesandmonitoring
: programs, theWOGevaluation hasresultedinthefollowing observations regarding plantsimilarity andthermalstratification:
1.Thermalstratification
(>100'F)hasbeenmeasuredonallsurgelinesforwhichmonitoring hasbeenperformed andwhichhavebeenreviewedbytheWOGtodate(7plants).2.Theamountofstratification measuredanditsvariation withtime(cycling) varies.Thisvariation hasbeenconservatively enveloped andapplicability demonstrated forplant-specific analyses.
Additional monitoring datarepresenting awiderrangeofsurgelineconfigurations maybeneededinordertodemonstrate theapplicability ofthesethermalstratification transients tootherWestinghouse units.3.Significant factorswhichcaninfluence thestructural effectsofstratification are:a.Locationanddesignofrigidsupportsand.restraints b.Pipelayoutgeometryandsizec.Typeandlocationofpipingcomponents 4.Althoughthematerialandfabrication techniques forWestinghouse surgelinesarereasonably consistent andofhighquality,thedesignparameters listedinitem3varyamongWestinghouse PWRs.Thisvariation indesignisprimarily aresultofplant-specific routingrequirements.
Thisvariability iscurrently beingexaminedinordertoasse'ssthefeasibility ofa.bounding analysisapproach.
Theseobservations developed throughtheongoingWOGprogram,indicatethatthedevelopment ofthermalstratification loadingsandtheevaluation offatigue,considering theseloadings, isacomplexprocess.Therefore, inordertoprecisely evaluatestratification, additional timeisneeded.Whilemoretimeisneededtoevaluatethestratification issueindetail,theNDEinspection historyatR.E.Ginna,aswellasallotherdomesticWestinghouse designedPWRs,hasnotrevealedanyserviceinduceddegradation inthesurgelinepipingthathasbeenattributed tothermalstratification.
Inaddition, alltheplant-specific analysesperformed todatethathaveincludedtheloadingsduetostratification andstripinghavevalidated the"leak-before-break" conceptandhavesubstantiated a40-yearplantlife.Thus,aprudentapproachforproviding adetailedevaluation oftheeffectsofsurgelinestratification wouldbetofollowtheWOGprogramgroupingevaluation recommendations andmonitorasdetermined tobeappropriate.
TheWOGhascompleted agroupingevaluation, forthepurposeofrecommending alistofadditional plantswherethermalmonitoring isneeded.Thetimerequiredforthisadditional monitoring willbedependent onplantoutageschedules.
Toassurethattheplantsafetyisnotcompromised withintherequested periodofscheduleextension, aJCOwillbeprepared.
TheJCO,whichiscurrently beingdeveloped, willbeavailable forstaffreview,ifdesired,within4monthsofreceiptoftheBulletin.
TheJCOwillutilizetheinformation, experience, andmonitoring dataobtainedthroughtheWOGprogram,andwillsupportthealternate schedulediscussed herein.Rochester GasandElectricCorporation herebyrequestsanalternate scheduletothatrequested inBulletin88-11.Ascheduleoftwoyears,fromreceiptoftheBulletin, isconsidered sufficient timetoobtainthenecessary additional monitoring data,definethermaltransients, performallrequiredanalysesandupdatethestressandfatigueanalysestoensurecompliance withapplicable codeandregulatory requirements.
Thisschedule, thoughdifferent fromthatrequested inaction1.bofBulletin88-11,isconsistent withtherequirement toupdatethestressandfatigueanalyseswithintwoyearsasstatedinaction1.do~eBulletin.
Atthistime,Rochester GasandElectricCorporation's requestforanalternate scheduleappliesonlytoitem1.bofNRCBulletin88-11.Rochester GasandElectricCorporation intendstocomplywithallotherrequirements oftheBulletin, butwillinformthestaffandjustifydifferences, ifappropriate.
Verytrulyyours,RobertC.MecedyGeneralManagerNuclearProduction RWEN024Subscribed andsworntobef'oremeonthis6thdayofMarch,1989.JAMESC.McGUiAENTARYPUSUC,StateoiNewYorkOuaIfiedinhbnroe CourttyMgCoinnission Exp@aOec.28,t9'zc:U.S.NuclearRegulatory Commission RegionI475Allendale RoadKingof'Prussia, PA19406GinnaSeniorResidentInspector}}

Revision as of 13:21, 29 June 2018

Discusses Objectives of Util Program to Confirm Pressurizer Surge Line Thermal Stratification Integrity,Per NRC Bulletin 88-011
ML17261A877
Person / Time
Site: Ginna Constellation icon.png
Issue date: 03/06/1989
From: MECREDY R C
ROCHESTER GAS & ELECTRIC CORP.
To: STAHLE C
NRC
References
IEB-88-011, IEB-88-11, NUDOCS 8903150532
Download: ML17261A877 (5)


Text

,gccE~~TED D1.'>1;jEIUTION DEMONSTR~TeIN SYSTEMREGULATORY INFORMATION DISTRIBUTION SYSTEM(RIDS)ACCESSION NBR:8903150532 DOC.DATE:

89/03/06NOTARIZED-YESDOCKETgFACIL'.50-244 RobertEmmetGinnaNuclearPlant,Unit1,Rochester G05000244AUTH.NAMEAUTHORAFFILIATION MECREDY,R.C.

Rochester Gas&ElectricCorp.RECIP.NAME RECIPIENT AFFILIATION STAHLE,C.

NRC-NoDetailedAffiliation Given

SUBJECT:

Discusses objectives ofutilprogramtoconfirmpressurizer surgelineintegrity,per NRCBulletin88-011.DISTRIBUTION CODE:IE11DCOPIESRECEIVED:LTR ENCLSIZE:TITLE:BulletinResponse(50DKT)NOTES:License Expdateinaccordance with10CFR2,2.109(9/19/72).

05000244RECIPIENT IDCODE/NAME PD1-3LASTAHLE,CINTERNAL:

AEOD/DOANRR/DEST/ADE 8HNRR/DEST/MEB 9HNRR/DOEA/GCB 11QJGkSQDLRB12GN1ILE01EXTERNAL:

LPDRNSICCOPIESLTTRENCL1011111111111111111111RECIPIENT IDCODE/NAME PD1-3PDAEOD/DSP/TPABNRR/DEST/ADS 7ENRR/DOEA/EAB 11NRR/DREP/EPB 10NUDOCS-ABSTRACT RES/DSIR/EIB NRCPDRCOPIESLTTRENCL111111111111111'.1NOTE'IOALL"RIDS"RECIPZEÃIS:

PLEASEHELPUSTOREDUCEWASTE!CONTACT'IHEDOCUMEMI'GÃIBOL DESK,RXMPl-37(EXT.20079)IOELQ~TEARKNAMEFRYDISTEKBVZIGN LISTSFORDOCt2KMIS YOUDGN~TNEEDfTOTALNUMBEROFCOPIESREQUIRED:

LTTR19ENCL18 March6,1989U.S.NuclearRegulatory Commission DocumentControlDeskAttn:Mr.CarlStahlePWRProjectDirectorate No.1Washington, D.C.20555

Subject:

NRCBulletinNo.88-11Alternate ScheduleforEvaluation ofPressurizer SurgeLineThermalStratification R.E.GinnaNuclearPowerPlantDocketNo.50-244

DearMr.Stahle:

OnDecember20,1988,theNRCissuedBulletinNo.88-11"Pressurizer SurgeLineThermalStratification".

Itrequestsalladdressees toestablish andimplement aprogramtoconfirmpressurizer surgelineintegrity inviewoftheoccurrence ofthermalstratification, andrequiresthemtoinformthestaffoftheactionstakentoresolvethisissue.Pursuanttosatisfying therequirements andschedules ofBulletin88-11,Rochester GasandElectricCorporation isparticipating inaprogramforpartialresolution ofthisissuethroughtheWestinghouse Owner'sGroup(WOG).TheWOGprogramwasapprovedattheOctober1988meetingandhasthefollowing objectives:

~DevelopagenericJustification forContinued Operation (JCO)toassurethatplantsafetyisnotcompromised whiletheeffectsofthermalstratification arebeingdetermined.

Collectandsummarize relevantdesign,operational, analytical, andtestdataforasmanyWOGplantsaspossible.

Inaddition, arepresentative

sampling, ofapproximately tenplants,willbeselectedtoperformareviewofplantrecordsandconductinterviews withoperations personnel.

~Evaluatedataandidentifyandprioritize significant parameters contributing tothisissue.Categorize (group)~~plplantsbasedontheseparameters.

w'0~~'203i5053239030'~PDFAGOCK0.":000244

~Recommend additional monitoring tosupplement theexistingtransient databaserequiredtoboundallWOGplants.Estimatetheeffectofthermalstratification onfatiguelifeasafunctionofkeyparameters.

~Recommend shorttermandlongtermactions.TheWOGprogramisdesignedtobenefitfromtheexperience gainedintheperformance ofseveralplant.-specific analysesonWestinghouse PWRsurgelines.Thesedetailedanalysesincludeddefinition ofrevisedthermaltransients (including stratification) andevaluations ofpipestress,fatigueusagefactor,thermalstriping, fatiguecrackgrowth,leak-before-break,andsupportloads.Theoverallanalytical approachusedinalloftheseanalyseshasbeenconsistent andhasbeenreviewed, indetail,bytheNRCstaff.Asignificant amountofsurgelinethermalmonitoring datahasbeenobtainedinsupportoftheseplant-specific analyses.

Additional surgelinethermalmonitoring andplantsystemdatacontinues tobemadeavailable withintheWOG,resulting inasteadilyincreasing database.

Asignificant amountofprogresshasbeenaccomplished towardmeetingtheseobjectives.

Todate,theWOGhascompleted approximately 80-odftheeffortofassembling plant-specific designinformation onalldomesticWestinghouse PWRs(55unitstotal);Theeffortwillestablish therangeofkeydesignparameters andpermitgroupingofplantsbasedontheseparameters.

Basedontheinformation assembled todate,andtheexperience gainedinplant-specific analysesandmonitoring

programs, theWOGevaluation hasresultedinthefollowing observations regarding plantsimilarity andthermalstratification:

1.Thermalstratification

(>100'F)hasbeenmeasuredonallsurgelinesforwhichmonitoring hasbeenperformed andwhichhavebeenreviewedbytheWOGtodate(7plants).2.Theamountofstratification measuredanditsvariation withtime(cycling) varies.Thisvariation hasbeenconservatively enveloped andapplicability demonstrated forplant-specific analyses.

Additional monitoring datarepresenting awiderrangeofsurgelineconfigurations maybeneededinordertodemonstrate theapplicability ofthesethermalstratification transients tootherWestinghouse units.3.Significant factorswhichcaninfluence thestructural effectsofstratification are:a.Locationanddesignofrigidsupportsand.restraints b.Pipelayoutgeometryandsizec.Typeandlocationofpipingcomponents 4.Althoughthematerialandfabrication techniques forWestinghouse surgelinesarereasonably consistent andofhighquality,thedesignparameters listedinitem3varyamongWestinghouse PWRs.Thisvariation indesignisprimarily aresultofplant-specific routingrequirements.

Thisvariability iscurrently beingexaminedinordertoasse'ssthefeasibility ofa.bounding analysisapproach.

Theseobservations developed throughtheongoingWOGprogram,indicatethatthedevelopment ofthermalstratification loadingsandtheevaluation offatigue,considering theseloadings, isacomplexprocess.Therefore, inordertoprecisely evaluatestratification, additional timeisneeded.Whilemoretimeisneededtoevaluatethestratification issueindetail,theNDEinspection historyatR.E.Ginna,aswellasallotherdomesticWestinghouse designedPWRs,hasnotrevealedanyserviceinduceddegradation inthesurgelinepipingthathasbeenattributed tothermalstratification.

Inaddition, alltheplant-specific analysesperformed todatethathaveincludedtheloadingsduetostratification andstripinghavevalidated the"leak-before-break" conceptandhavesubstantiated a40-yearplantlife.Thus,aprudentapproachforproviding adetailedevaluation oftheeffectsofsurgelinestratification wouldbetofollowtheWOGprogramgroupingevaluation recommendations andmonitorasdetermined tobeappropriate.

TheWOGhascompleted agroupingevaluation, forthepurposeofrecommending alistofadditional plantswherethermalmonitoring isneeded.Thetimerequiredforthisadditional monitoring willbedependent onplantoutageschedules.

Toassurethattheplantsafetyisnotcompromised withintherequested periodofscheduleextension, aJCOwillbeprepared.

TheJCO,whichiscurrently beingdeveloped, willbeavailable forstaffreview,ifdesired,within4monthsofreceiptoftheBulletin.

TheJCOwillutilizetheinformation, experience, andmonitoring dataobtainedthroughtheWOGprogram,andwillsupportthealternate schedulediscussed herein.Rochester GasandElectricCorporation herebyrequestsanalternate scheduletothatrequested inBulletin88-11.Ascheduleoftwoyears,fromreceiptoftheBulletin, isconsidered sufficient timetoobtainthenecessary additional monitoring data,definethermaltransients, performallrequiredanalysesandupdatethestressandfatigueanalysestoensurecompliance withapplicable codeandregulatory requirements.

Thisschedule, thoughdifferent fromthatrequested inaction1.bofBulletin88-11,isconsistent withtherequirement toupdatethestressandfatigueanalyseswithintwoyearsasstatedinaction1.do~eBulletin.

Atthistime,Rochester GasandElectricCorporation's requestforanalternate scheduleappliesonlytoitem1.bofNRCBulletin88-11.Rochester GasandElectricCorporation intendstocomplywithallotherrequirements oftheBulletin, butwillinformthestaffandjustifydifferences, ifappropriate.

Verytrulyyours,RobertC.MecedyGeneralManagerNuclearProduction RWEN024Subscribed andsworntobef'oremeonthis6thdayofMarch,1989.JAMESC.McGUiAENTARYPUSUC,StateoiNewYorkOuaIfiedinhbnroe CourttyMgCoinnission Exp@aOec.28,t9'zc:U.S.NuclearRegulatory Commission RegionI475Allendale RoadKingof'Prussia, PA19406GinnaSeniorResidentInspector